The extrusion blow molding process consists of a blow molding process in which a parison (a tubular sleeve) formed by extrusion is used instead of a preform. This parison, usually made of high-density polyethylene (HDPE), can be multilayer (co-extrusion) to provide the container with effective gas and vapor barriers or to incorporate recycled material, for example.
The parison is hermetically sealed at the bottom due to the clamping action of the mold as it closes and withdraws. The mold then moves to the blowing stage, where it is allowed to cool and the part is ejected.
Extrusion blow molding machines can be equipped with 1 or 2 sets of molds. Models with 2 sets of molds have a higher production output, since while the parison is being formed inside one of the molds, the other goes through the blowing and cooling phase.
The resulting container can be translucent or opaque, and its capacity is very flexible, even up to 200-liter containers can be produced. For large containers, the addition of cooling systems for the blowing air is recommended to reduce cycle times (cooling phase) and thus increase productivity.
PET Packaging Network (PPN) can provide this blow molding solution. The technology has a wide range of applications and is used in the dairy and food/beverage industries, as well as in the cosmetics, mineral oil, and chemical industries, among others.